Extraction apparatus

Abstract

An extraction apparatus (20) for a cutting machine (10). The extraction apparatus (20) comprises first and second portions (21, 22) rotatable one relative to the other for angular movement between two opposed positions. A slidable coupling (27) defines a fluid flow path (29) for fluid communication between the first and second portions (21, 22) during said angular movement between the two opposed positions, whereby fluid can flow from the interior (45) of the first portion (21) into the second portion (22). The slidable coupling (27) comprises first and second coupling sections (61, 62) slidable one with respect to the other. The second coupling section (62) is hollow to define an open interior (63). The first coupling section (61) defines a duct (65) opening onto the interior (63) of the second coupling section (62), whereby the duct (65) and the interior (63) of the second coupling section (62) cooperate to define the fluid flow path (29).

The invention claimed is: 
     
       1. An extraction apparatus comprising first and second portions, the first portion defining an interior for receiving a portion of a rotary tool element having an axis of rotation and having an open end defining an opening through which the rotary tool element extends and having a peripheral edge which bounds the opening and defines a contact face for engagement with and sliding movement over a surface;
 wherein said first portion is rotatable relative to the second portion for angular movement between two opposed positions whilst the first and second portions are configured to define a flow path for fluid communication during said angular movement between the two opposed positions whereby fluid can flow from the interior of the first portion into the second portion at any angular position between the two opposed positions; 
 wherein said first portion is rotatable relative to the second portion about said axis of rotation of the rotary tool element for enabling said contact face to maintain engagement with the surface during said sliding movement of the contact face over the surface; 
 wherein the first and second portions are configured to define a slidable coupling providing the fluid flow path, the slidable coupling being adapted to accommodate said angular movement between the first and second portions; 
 wherein the slidable coupling comprises a first coupling section and a second coupling section slidable one with respect to the other, the second coupling section being hollow to define an open interior, and the first coupling section defining a duct opening onto the interior of the second coupling section, whereby the duct and the interior of the second coupling section cooperate to define the fluid flow path; and 
 wherein the first coupling section is configured as a tubular section defining the duct, and the second coupling section is configured as a sleeve section, the tubular section being slidably received in the sleeve section, whereby the slidable coupling is operable to undergo extension and contraction in a telescopic manner. 
 
     
     
       2. The extraction apparatus according to  claim 1  wherein the sleeve section is configured to accommodate angular movement of the first portion as the first coupling section moves slidably with respect to the second coupling section. 
     
     
       3. The extraction apparatus according to  claim 2  wherein the sleeve section incorporates an axial opening for accommodating the first portion during angular movement thereof as the tubular section defining the first coupling section moves slidably with respect to the sleeve section. 
     
     
       4. The extraction apparatus according to  claim 1  wherein the first coupling section and the second coupling section are configured to accommodate said angular movement between the first and second portions. 
     
     
       5. The extraction apparatus according to  claim 1  wherein the first coupling section is provided on the first portion and the second coupling section is provided on the second portion. 
     
     
       6. The extraction apparatus according to  claim 1  wherein the first portion comprises a peripheral wall bounding the interior of the first portion, and the first coupling section is disposed adjacent a portion of the peripheral wall on the opposed side thereof with respect to the interior, the flow path being in fluid communication with the interior of the first portion through an intervening portion of the peripheral wall. 
     
     
       7. The extraction apparatus according to  claim 6  wherein the interior of the first portion is in fluid communication with the flow path by way of one or more openings provided in the intervening portion of the peripheral wall. 
     
     
       8. The extraction apparatus according to  claim 7  wherein the one or more openings provided in the intervening portion of the peripheral wall comprises an aperture in the peripheral wall, the aperture being disposed adjacent an open end of the first portion through which the rotary tool element can extend. 
     
     
       9. The extraction apparatus according to  claim 7  wherein the one or more openings provided in the peripheral wall comprise one or more ports in the peripheral wall configured to deflect or otherwise direct dust and other debris generated through operation of the rotary tool element together with any associated slurry into the flow path within the sliding coupling. 
     
     
       10. The extraction apparatus according to  claim 1  wherein the rotary tool element extends through the opening at all angular positions of the first portion between the two opposed positions. 
     
     
       11. The extraction apparatus according to  claim 10  wherein the open end of the first portion is an entry into the flow path at all angular positions between the two opposed positions. 
     
     
       12. The extraction apparatus according to  claim 1  wherein the first portion is configured as a shroud disposed about a portion of the rotary tool element. 
     
     
       13. The extraction apparatus according to  claim 1  wherein the first portion is a solitary guard piece that rotates within the second portion. 
     
     
       14. The extraction apparatus according to  claim 1  wherein a proportion of the rotary tool element that extends through the opening is constant at all angular positions between the two opposed positions. 
     
     
       15. A machine for performing a working operation, the machine having an extraction apparatus according to  claim 1 . 
     
     
       16. The machine according to  claim 15  comprising a work head, wherein the second portion is attached to or formed integrally with the work head and the first portion is angularly movable with respect to the second portion. 
     
     
       17. A method of performing a working operation, the method comprising use of a machine according to  claim 15 .